Weather resistant composition



Patented June 2 ,1949

WEATHER RESISTANT COMPOSITION mu, Tucker c1111, Fairhaven, Mass" we. bymesne assignments, to Standard Oil Development Company, a corporation oiDelaware No Drawing. Application November 8, 1944, Serial No. 582,571

This invention relates to a new weather resistant composition suitablefor a wide variety of uses. More particularly, this invention relates toa novel elastic composition which can be processed and fabricated withconventional rubber manufacturing equipment.

An object of this invention is to produce a new composition of matterunusually resistant to sunlight and outdoor weather exposure. Anotherobject is to provide an elastic material for treating cloth which willbe resistant to sunlight and at the same time will not crack on flexingat low temperatures. A further object is a new material which willprocess readily without the necessity of excessive temperatures duringmixing or preparation on. a mill or in a Banbury mixer.

3 Claims. (01. 260-233)- added: 40 parts of carbon black; 20 parts ofdioctyl phthalate; 30 parts of tricresyl phosphate;

v parts of dibenzyl sebacate; 8 parts of zinc 1.5 parts of paraflinStill another object is a composition very resistant to oils and fats.Another object is a composition resistant to ozone, corona effect,andelectrical current. A further object is to advance the prior art.Other objects will appear hereinafter. i

My invention consists essentially of intimately associating a rubberybutadiene acrylonitrile copolymer and a polyvinyl acetate resin.

The butadiene acrylic acid nitrile copolymer which I prefer is onecontaining 74% of butadiene and 26% of acrylic'acid' nitrile; however,any copolymer of butadiene and acrylic acid nitrile regardless of therelative proportions is intended in the scope of my invention. As thepolyvinyl acetate resins employed in my inventions arepolymerized vinylacetate (CH'aCOOCHCH2)=, and any resin or substance which is a copolymerof vinyl acetate regardless orv the relative proportions of .the vinylacetate and the copolymerizing substance. I prefer in. this invention acopolymer resin formed by reacting 99 to vinyl acetate with 1 to 85% ofa copolymerizing substance. However desirable and novel results can beobtained with copolymers consisting of as little as 5% of vinyl acetate.For example, the copolymer of 5 partsof vinyl acetate and 95 parts ofvinyl alcohol. I v

The following examples will serve to illustrate my invention.

Exmnr: 1

100 parts of polyvinyl acetate resin having a softening point ofapproximately 44 centigrad'e was added on the form of a powder to 100parts of butadiene acrylonitrile copolymer on very tight mill rolls atabout 200 Fahrenheit. The mix.

was milled until intimate homogeneous associaa copolymer of vinylacetate and vinyl chloride,

oxide; 2 parts of sulfur; 1.5 parts of benzothiazyl disulflde; 1.5partszof phenyl betanaphthylamine; wax; and 1.5 parts of stearic acid. i

The resultant mixture was milled till allmaterials werehomogeneouslydispersed and then vulcanized for 60 minutes at 305 Fahrenheit underpressure with results as enumerated in Table 1.

Table 1 Tensile strength. 2405 lbs.

Ultimate elongation 480% lllow temperature flexibility--- 78 FahrenheitSunlight exposure (3 weeks) No cracks Oil exposure (3 weeks at 70Fahrenheit) .j. No change The sunlight exposure was conducted withstrips under a static tension of 15% elongation. A control .stripcomposed entirely 'of a butadiene acrylon'itrile copolymer compoundshowed cracking in 9 days.

per sq. in.

i Exmns 2 1 100 parts of a vinyl acetate resin substantially wereintimately mixed by adding to 100 parts of butadiene acrylonitrile'copolymer on a conventional rubber mill at approximately 160 Fahrenheit.After milling for 12' minutes, the batch was tion was obtained and thefollowing materials removed and remllled on tight mill rolls thefollowing day at approximately 230 Fahrenheit until homogeneity wasobtained. Then the following ingredients wereadded: parts of channelblack; 55 parts of tricresyl phosphate; 20

parts of dicapryl phthalate; 2, parts of sulfur; 10 parts of zinc oxide;2 parts of stearic acid; 2 parts of hard petroleum wax; 2 parts ofmercaptobenzythiazole; and 1 part of phenyl beta naphthyl amine.

The resultant mixture was vulcanized 60. minutes at 305 Fahrenheit withresults as illustrated in Table 2.

' Table 2 Tensilestrength 3110 lbs. per sq. in. Ultimate elongation 565%Low temperature flexibility '75 Fahrenheit Sunlightexposure (3 weeks) Nocracks The sunlight exposure was conducted in the same manner as thesunlight exposure shown in Table 1.

a Oil exposure (3 weeks at '10 1".) No change Water absorption (1 weeksat 70 F.) 0.12%

ing (not intended to be limitative):

Animal fatty acids Antimony sulfide Asbestos Barium carbonate Cottonseedfatty acid Barytes Fish oil acid, hydrogen-Bentonite ated Hydrated limeLauric acid Litharge Lead silicate Magnesia Oleic acid Palm oil fattyacid Clay Cotton flock Sodium laurate Whitin Zinc stearate Zincpalmitate Zinc oleate Paraflln Petroleum waxes Sodium bicarbonateFactice Zinc sulfide Titanium dioxide Organic colors Chrome oxides Leadchromate Cadmium sulfide Ultramarine blue Cadmium salts Calcium stearateIron oxide Lithol toners Cumar-indene resins Coumarone resins Granulatedcork I Mineral rubber Gilsonite Asphalt Suliurized oils Oxidized oilsKaolin Mica Aluminum silicate I claim: 1. A vulcanized co Blane flxeCalcium. silicate Chalk Gypsum Diatomaceous earth Bone glue GraphiteLignin Magnesium carbonate Magnesium silicate Pumice Silica Slate TalcWood flour Zinc carbonate Calcined carbon Carbon oxides Shellac ZeinSoya bean oil Beeswax Pitch Pine tar Pine oil Castor oil Coal tar oilsCocoanut oil fatty acid Wool grease Dialkyl phthalates Dialkyl sebacatesDiaryl phthalates Dialkyl sebacates Trialkyl (or aryl) phosphates Allrylpropionates Fat acids Natural waxes Rosin oil Tar oil Vulcanized oilsmposition of matter characterized by superior sunlight resistance andultimate elongation of at least 480 percent and a armsoa tensilestrength of at least 2405 pounds per square inch, said compositionconsisting 0!: 100 parts of a rubbery butadiene-acrylonitrile copolymermixed homogeneously with a substantially equal amount of a polyvinylacetate resin having a softening point of approximately 44 0.; 40 partsof carbon black; 20 parts of dioctyl phthalate; 30 parts of tricresylphosphate; 10 parts of dibenzyl sebacate; 8 parts of zinc oxide; 2 partsof sulfur; 1.5 parts 0! benzothiazyl disulfide; 1.5 parts of phenyl betanaphthyla-mine; 1.5 parts of paraflln wax and 1.5 parts of stearic acid.

2. A vulcanized composition of matter characterized by superior sunlightresistance and ultimate elongation of at least 480% and a tensilestrength of at least 2405 pounds per square inch, said compositionconsisting of: 100 parts of a rubbery butadiene-acrylonitrlle copolymer,mixed homogeneously with a substantially equal amount of a resinouspolymer of vinyl acetate; 40 parts of carbon black; 20 parts of dioctylphthalate; 30 parts of tricresyl phosphate; 10 parts of dibenzylsebacate; 8 parts of zinc oxide 2 parts of sulfur; 1.5 parts ofbenzothiazyldisulfide; 1.5 parts of phenyl beta naphthylamine; 1.5 partsof paraflin wax; 1.5 parts of stearic acid.

3. A vulcanized composition of matter characterized by superior sunlightresistance and ultimate elongation of at least 480% and a tensilestrength of at least 2405 pounds per square inch, said compositionconsisting of: 100 parts of a rubbery butadiene-acrylonitrile copolymermixed homogeneously with a substantially equal amount of a resinouscopolymer of 5 parts of vinyl acetate and parts of vinyl alcohol; 40parts of carbon black; 20 parts of dioctyl phthalate; 30 parts oftricresyl phosphate; 10 parts of dibenzyl sebacate; 8 parts of zincoxide; 2 parts of sulfur; 1.5 parts of benzothiazyl disulfide; 1.5 partsof phenyl beta naphthylamine; 1.5 parts of paraffin wax; 1.5 parts ofstearic acid.

PHILIP TUCKER GIDLEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

